Long-term paracetamol use could increase the risk of heart disease and strokes in people with high blood pressure, a study found.
Paracetamol is a common pain killer used to treat aches and pain. Paracetamol use is often short-term, however, if you suffer from a condition such as chronic pain, patients may be supplied a paracetamol prescription. However, the researchers are recommending that patients with extended paracetamol use should opt for the lowest effective dose for the shortest time possible.
The researchers from the University of Edinburgh published their findings in the scientific journal Circulation.
Long-term paracetamol use
The study, which is the first large randomised clinical trial, addresses long-term paracetamol use and complements earlier work in observational studies. Observational studies have suggested that paracetamol use may increase blood pressure, clinical trials are lacking.
Paracetamol was often suggested as a safer alternative to another class of painkillers called non-steroidal anti-inflammatory drugs (NSAIDs), which are known to increase blood pressure and risk of heart disease.
“We would recommend that clinicians start with a low dose of paracetamol, and increase the dose in stages, going no higher than needed to control pain. Given the substantial rises in blood pressure seen in some of our patients, there may be a benefit for clinicians to keep a closer eye on blood pressure in people with high blood pressure who newly start paracetamol for chronic pain,” commented Professor David Webb, Principal Investigator and Chair of Therapeutics and Clinical Pharmacology at the University of Edinburgh.
Clinical trial
In the latest study, 110 patients with a history of high blood pressure were prescribed one gram of paracetamol four times a day – a routinely prescribed dose in patients with chronic pain – or a matched placebo for two weeks. All patients received both treatments in a randomised, double-blind order. Those with the prescribed paracetamol use saw a significant increase in their blood pressure, compared with those taking the placebo.
This rise was like that seen with non-steroidal anti-inflammatory drugs and might be expected to increase the risk of heart disease or stroke by 20%, the researchers stated. Furthermore, the team of experts said the findings should lead to a review of long-term paracetamol use and prescriptions of the drug to patients with a specific focus on those with existing high blood pressure, or those at risk of heart disease and stroke.
“This study clearly shows that paracetamol – the world’s most used drug – increases blood pressure, one of the most important risk factors for heart attacks and strokes. Doctors and patients together should consider the risks versus the benefits of long-term paracetamol use, especially in patients at risk of cardiovascular disease,” commented Professor James Dear, Chair of Clinical Pharmacology at the University of Edinburgh.
“This is not about short-term use of paracetamol for headaches or fever, which is, of course, fine – but it does indicate a newly discovered risk for people who take it regularly over the longer term, usually for chronic pain,” said Dr Iain MacIntyre, Lead Investigator and Consultant in Clinical Pharmacology and Nephrology at NHS Lothian.